(369e) Flow Synthesis: An Improved Path to Market for Nanoparticle Catalysts

Today, solution-phase technologies for high quality colloidal inorganic nanoparticle fabrication remain at the bench scale, with a cost that reflects the limited throughput and labor intensity of a by-hand process. This is because small bench-scale reactions can achieve uniform mixing conditions and uniform temperature throughout the reaction vessel: essential conditions for producing uniform, high-quality nanoparticles. Standard, large-volume industrial chemical reactors lack uniform mixing and uniform temperature; they would produce low-quality particles with heterogeneous morphologies and are therefore an inappropriate route to the scale-up of high-quality inorganic nanoparticle manufacturing. On the other hand, uniformity of temperature and mixing is trivial in a droplet microfluidic reactor. The high surface-area-to-volume ratio of a microchannel guarantees uniform temperature throughout the reaction volume, and convective droplet mixing rapidly homogenizes the reaction mixture. Our recent efforts have shown that microfluidic droplet formats are appropriate for producing a wide range of inorganic nanoparticles, including particles made from precious metals, alloys, carbides, and phosphides. Ultimately, in order to produce particles cost-effectively at large scale, micro- or millifluidic reactors must be operated in a parallel configuration, with many reactors working together simultaneously and identically to produce nanoparticles. Here, we present a rational, science driven approach to scaling microfluidic nanomanufacturing by massive parallelization.